Oil burner pump



Jan. 18, 1955 D. L. GETZ ETAL 2,699,727

7 on. BURNER PUMP Filed Oct. 4, 1950 5 Sheets-Sheet l o o 5 Q a I n f, 4 x m 11 14 ll Swami/ow DELMOND L. GETZ ROBERT 0. HEDGES Z M9-M ATTORNEYS Jan. 18, 1955 D. L. GETZ ET AL OIL BURNER PUMP 3 Sheets-Sheet 2 Filed Oct. 4, 1950 3 T6 Q Ma T m mw MR 7 mww 0 6 7w I H ATTORNEYS Jan. 18, 1955 D. L. GETZ ETAL OIL BURNER PUMP 3 Sheets-Sheet 5 Filed Oct. 4, 1950 DELMOND L.GETZ Q ROBERT 0. HEDGES ATTOR N EYJ United States Patent 2,699,727 on BURN m N 1MP" Delinoiid L. Gets and obm o. Hedges, Springfield, Ohio, assignors to The Steel Products Engineering Coin {rainy-Springfield, Ohio, a corporation of Ohio Application" October 4, 1950, SeriaPNo. 188,451 7 Claims. (Cl. 103-45 This inventionrelates to oil burners for heating purposes and' the like; The invention has particular relation to an atomizing pump, adapted for incorporation in anpoil burner for mixing liquid fuelwith air for transmission to the combustion head of the burner at a desired pressure.

One'of the principal objects of the invention isto provide an atomizing pumpfor anoil burner which includes an eccentric rotor for iinpelling themixture of fuel from the suction port of thepump to its'discharge port, and which also includes a valve of simple construction mounted for rocking movement in response to' rotation of therotor to control communication between the inlet and outlet-p'orts of the pump.

Another object is to provide an atomizing pump of theabove characteristics in' which" the valve includes cylindrically curved portions engaging" cornplementarily curved walls of the valve chamberfor controlling communicationtherethrough between the suctioni and dis charge ports ofthepump'and in which a simple arrangement of a'torsion spring maintains the valve atall times inthe proper working engagementwith the rotor.

It is also an object of'- the invention to provide an atomizingt pump for an oil burner which includes eccentric rotor and a" rocking valve operated by engagement with the rotor to control communication between the suctiondischarge ports of' the pump and in which the valve has a portion cut away to prevent stickingi or cloggihg'resulting from dirt'o'r other solidmaterial wiped over the edge thereof fromtlie rotor. o

Other objects and advantages ofthe invention will be apparent 1 from the following description, the accompanymg drawings and the appendedclaim's.

Fig. 1 is a view partly in side elevationan'd partly broken away: showing' 'ah oil burnerinaccordance with the inventioml brokeii away to illustrate" details of internal construe ti'on;

in'g= the "relative positions "of ithe" pa'rts ifollowing' rotation of th'e rotorthr0ugl1*180 from '1tspos1t1on as shown in Fig. 10 is adet'ailvievvin section on the'line 10-10" ferred embodimenv ofthe invention, Figs. 1 and 2' PatentNo; 2,632,499," issu'ed March 2 4, i953 of which the present application is a continuation in part. Theoil- 'burner includes a"m"ain"-casing113 having a base 14 2,699,727 Patented an. i

2 damper 22 is provided for regulating the supply of air to the blower 1 7 The oil from the supply tank (not shown) is initially admitted to the metering pump by way of an inlet connection 24, and the pump 15 supplies this oil at a metered rate to the atomizing pump 16, where it ismixed with air and then passed to a flow stabilizing device 25 by meansof a pipe or tube 26.

In the flow stabilizing device 25, as is described in detail in the above Patent No. 2,632,499, the atomized mixture is separated into air and liquid fuel for separate transmission to the nozzle in the combustion head 31 at the outer end of the blast tube 32. The air flows to the nozzle through a tube 33 to serve as primary air for mixture with the oil, which flows to the nozzle through a smaller tube 34' within, the, tube 33. At the nozzle, the liquid oil and primary air are mixed and ignited by a spark induced betweenthe electrodes 35, which are provided with the proper high tension cur rent' from the transformer 36 on casing 13, and second; ary air is supplied to the combustion head from the blower 17, the combustion head 31 having fins 37 thereon for caus ng the secondary air to'swirl as it is discharged from theblast tube. p p

The construction and' operation of the air atomiziiig pump are shownin detail in Figs. 3 to 10. The'pump housing 40" is formed with a pair of overlapping cylin; drical chambers 41a11d42 extending completely theref through, the chamber 41 being of larger diameter than the,chamber 42. These chambers are closed at their outer ends by gaskets 43 and 44, which are positioned between housing 40 and the oil metering'pump' 15 and air damper 22', respectively, and arecemented or otherwise'sealedto housing 40. Thegaskets being removed in Fig. 6' for greater clarity of illustration; A cylin} dric'al rotor 45' of smaller diameter than chamber41 is' mounted therein for rotation with shaft. 21 eccentri cally" of chamber 41, the rotor being keyed or otherwise secured to the shaft at 46, and the rotor is partiallyiholq lowed on either side thereof at 47 for purposes of bal ance.

The oil and'air passlthrough a series of ports and'pasf sages in the pump housing40. The oil initially "enters the pump through aport 50in the side of the. housing and the gasket 44', andit flows therefrom through a passage 51'whichopen's intochambe'r 41 adjacent chain-,1 bet 42, theouter end of passage 51 beingclosed bya screw? plug 52. The port 50 registers with a discharge portin the'housing ofoil pump 15 as described in greater detailinthe' aboveTatent No; 2,632,499 and in our co; pending application Serial No. 188,450 filed of evendate herewithfand assigned to the same assignee as this,applic'ation. The oilptimp 15 also incorporates the mai'nf shuto'ifyalve 5 5 for the oil burner, the valve being held normally closed by'a spring 56 as shown in Fig; ,2 and including apiston S'I in the pressure chamber 58 mov; ableiagainst spring'j56 bypressure supplied from theair, pump 16 as described hereinafter as well as in the above copend ingfapplications. H

The airformixing with the oil in chamber 41 enters the pump initially througha chamber 60 in the top oi the housing which is provided with a muflier unit indicated" generally at 61, and from the muflier the air flows, througha passage 62 in to the passageSl. A discharge orloutlet passage 6Sis provided in the, opposite side of the pump housing 4-9 from inlet passage 51, the discharge passage 65 opening into chamber 42 and communicating therethrpugh with chamber 41 as shown in,Fig., 3. fitting 66 is mounted in the outer endof outlet 65 toprovide aconnection to the pipe or tube ZtTleadingto the flow stabilizer 2 5 as described.

A, valve 7S"iS mounted for rocking movementin chamber 42*to control communicationbetween' theinle't passage '51 and the 'outlet passage 65 as the"rotor 45" revolves." This valve is mountedbn a pin ordowel7'l positionedconcentric with the chamber '42 and supported atniteendsinthehousings ofthe pump '15and air damper 22 "as shown*";in"Fig."4. ,The'valve includes afrounded: tipirpbrtionfiil adapted "to engage 'the peripheral. surface ofithe' *rotor 45. Afportion82'ofthevalveadjacentithe tip'portion-60 "is cylindrically 'convex about substantiallythe same radius of curvature as the chamber 42 for close engagement with the periphery of this chamber as the valve rocks, and another portion 83 of the valve approximately opposite this portion 82 is similarly cylindrically convex for engagement with the periphery of chamber 42. The lower portion of the valve which receives the dowel 77 is cut away at 84 to provide space for receiving the end portions of a generally U-shaped or horseshoe type torsion spring 85, as shown in Figs. 3 and 4, which provides a constant biasing force urging the valve 75 in counterclockwise direction as viewed in Figs. 3 and 5 to maintain the valve tip 80 in constant engagement with the rotor 45. Also, the housing 40 is provided with a threaded passage 86 opening into the lower part of chamber 42, and a plunger-88 is threaded in this passage for engagement with the mid portion of spring 85 to regulate the biasing force thereof on valve 75 as desired, the plunger 88 being protected by a screw plug 89 as shown in Fig. 3.

The valve 75 is thus at all times eifective to prevent communication between the inlet passage 51 and the outlet passage 65 through the chamber 42 or the lower part of the chamber 41. The only communication from inlet 51 to outlet 65 is thus through chamber 41 in the direction'of rotation of the rotor 45. During'the major part of each revolution, the rotor acts to separate chamber 41 into two portions, identified as 41a and 41b in Fig. 5, which constantly vary in size, and it creates a suction efiect in the chamber portion 41a while at the same time exerting pressure in the chamber portion 41b as it decreases the size of the latter chamber portion and thus forces the contents thereof out through the outlet passage 65.

The relative sizes of the two chambers and the rotor 45 are such as to provide a total capacity for the chamber portions 41a and 41b which is in excess of the effective volumetric output of the oil pump for a single revolution of shaft 21. As a result, the oil from the metering pump which is received in the chamber portion 41a does not fill this space when this chamber portion reaches its maximum capacity in the position of the rotor shown in Fig. 3, and accordingly a quantity of air is, also taken in suflicient to make up the deficiency. The resulting mixture of oil and air is transferred to the chamber 41b on the next revolution of the rotor and is then forced out through the discharge passage 65.

As pointed out, the valve 75 rocks in chamber 42 as the rotor 45 revolves and thus prevents communication between the inlet and outlet passages of the pump except through the chamber 41 in the direction of rotation of the rotor, the biasing effect of the spring 85 being sufficient to maintain the valve tip 80 at all times in sealing contact with the periphery of the rotor. The rotor accordingly has continuous wiping contact with the valve tip 80, and in order to prevent clogging or sticking of the valve such as might be caused by dirt or other foreign material transferred to the valve from the rotor, the side portion 90 of the valve between the tip 80 and the convex portion 83 is cut away to provide substantial clearance between this part of the valve and the inner surface of chamber 42 when the valve is at or near its limit'of clockwise rocking movement as viewed in Fig. 3, thus assuring a continuous flow of fluid to the nozzle for effective operation of the burner.

The construction and arrangement of the valve 75 in the pump as shown are especially advantageous in assuring proper action over a wide range of operating conditions, and especially in assuring proper cooperative action between the tip portion 80 and the rotor without excessive friction even at relatively high pressures and suctions. This result derives to a considerable extent from the balanced mounting of the valve on the pivot 77 concentric with chamber 42, which with the valve proportioned as shown causes the pressures and suctions on each exposed surface of the valve to be elfectively equalized relative to the pivot 77 in all positions of the valve. This in turn assures substantially constant pressure between tip portion 80 and the rotor in all positions of the parts over the entire range of suctions and pressures effective on the valve in operation. In addition, the balanced mounting of the spring 85 about the pivot 77 for the valve is a further aid in maintaining proper operation of the valve, since with this arrangement there is a minimum of side thrust such as could result if the spring were mounted away from the pivot axis of the valve, and thus stabilizer 25.

4 there is minimum tendency for excessive wear on either the spring or the valve.

In order to provide pressure for operating the pisto 57 and shutoff valve 55 in pump 15, a groove 99 is formed in the surface of housing 40 and connects at one end with the passage 65 through a port 100. A port 101 leads from the groove 99 through the gasket 44 and is adapted to register with a corresponding port in the housing of the oil pump 15 leading to the pressure side of the piston 57 as described in the above copending applications. Another port 103 in housing 40 and gasket 44 is adapted to register with a port in the, housing of oil pump 15 leading from the low pressure side of piston 57, and the port 103 is connected by a groove 104 in housing 40 and a port 105 with the inlet passage 51. The several holes 106 and 107 in the housing 40 are to receive bolts'or dowels for securing the air pump 16 in proper relation with the oil pump 15 and other parts of the burner.

An adjustable control is provided for the output pressure of the pump 16. The groove 99 from the discharge passage 60 is connected by passage 110 with a chamber 111 in the front of housing 40, and the chamber 111 is in turn connected with groove 104 by passages 112 and 113 as shown in Fig. 7. ,The passage 113 is provided with a tapered outer end 114 which serves as a seat for a needle valve 115 threaded in the outer end of chamber 111 and protected by a screw plug 116. The valve 115 may accordingly be adjusted to provide variable communication from the discharge side of the pump to its suction side and thus to effect recycling of a correspondinglg variable amount of the output of the pump as desire In the operation of the oil burner as a whole, as soon as the motor 20 is started, it sets the two pumps 15 and 16 in operation, and the pressure from the atomizing pump 16 is supplied as described to the pressure chamber 58 to move the valve 55 against the spring 56 to its open position, thus allowing oil to flow to the pumping mechanism of the metering pump 15. This oil is then supplied by the pump 15 to the atomizing pump 16 as described for mixture with air and delivery to the flow motor 20, the pressure supply to the chamber 58 is cut off, and accordingly the spring 56 returns the valve 55 to its closed position.

While the form of apparatus therein described constitutes a preferred embodiment of the invention, 1t 1s to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. An atomizing pump adapted for use in an oil burner comprising a main body having a pair of over-lapping cylindrical chambers therein of different diameters, means forming a discharge outlet from the smaller of said chambers, means forming an inlet for air and for oil to said larger chamber on the opposite side of said body from said outlet, a rotor of smaller diameter than said larger chamber mounted therein for rotation eccentrically thereof, a valve located in the smaller of said chambers, a pin in said smaller chamber forming a pivot supporting said valve for rocking movement, said valve including a portion arranged for continuous engagement with the periphery of said smaller chamber to prevent communication between said inlet and said outlet through said smaller chamber, said valve including a tip portion adapted to engage the periphery of said rotor, means biasing said valve into continuous contact of said tip portion thereof with said rotor to prevent the passage of fluid between said valve and said rotor as said valve rocks in response to rotation of said rotor, a portion of said valve adjacent said tip portion thereof on the pressure side of said valve being cut away to provide means preventing clogging or sticking of said valve by solid material transferred thereto from said rotor, and

said pin being located substantially concentric with said smaller chamber to maintain substantial equalization of the pressures'on said valve with relation to the pivotal axis thereof.

2. An atomizing pump adapted for use in an oil burner comprising a main .body having a pair of overlapping cylindrical chambers therein of diiferent diameters, means forming adischarge outlet from thesmaller of said chambers, means forming an inlet for air and for oil to said When the burner is shut off, by stopping larger chamber on the opposite side of said body from said outlet, a rotor of smaller diameter than said larger chamber mounted therein for rotation eccentrically thereof, a valve located in the smaller of said chambers, a pin in said smaller chamber forming a pivot supporting said valve for rocking movement, said valve including a portion arranged for continuous engagement with the periphery of said smaller chamber to prevent communi' cation between said inlet and said outlet through said smaller chamber, said valve including a tip portion adapted to engage the periphery of said rotor, means biasing said valve into continuous contact of said tip portion thereof with said rotor to prevent communication therebetween between said inlet and said outlet as said valve rocks in response to rotation of said rotor, a torsion spring located in said smaller chamber for biasing said valve into continuous contact of said tip portion thereof with said rotor to prevent the passage of fluid between said valve and said rotor as said valve rocks in response to rotation of said rotor, said pin being located substantially concentric with said smaller chamber to maintain substantial equalization of the pressures on said valve with relation to the pivotal axis thereof, and said torsion spring being mounted on said pin to provide a balanced bias about the pivotal axis of said valve with substantial freedom from side thrust.

3. An atomizing pump adapted for use in an oil burner of the character described including a metering pump having a pressure operated shutoff valve therein provided with a pressure responsive operating member, said atomizing pump comprising a main body having a chamber therein, means forming a discharge outlet from said chamber, means forming an inlet for air and for oil to said chamber, means in said chamber for impelling fluid from said inlet to said outlet, means in said main body for connecting said outlet with the pressure side of said pressure responsive member in said metering pump, and means in said main body for connecting said inlet with the low pressure side of said pressure responsive member in said metering pump.

An atomizing pump adapted for use in an oil burner of the character described including a metering pump having a pressure operated shutoff valve therein provided with a pressure responsive operating member, said atomizing pump comprising a main body having a chamber therein, means forming a discharge outlet from said chamber, means forming an inlet for air and for oil to said chamber, means in said chamber for impelling fluid from said inlet to said outlet, means in said main body forming a by-pass connection between said inlet and said outlet, a valve in said main body for regulating the passage of fluid through said by-pass connection in accordance with the desired output pressure of said pump, means in said main body for connecting the high pressure side of said by-pass connection with the pressure side of said pressure responsive member in said metering pump, and means in said main body for connecting the low pressure side of said by-pass connection with the low pressure side of said pressure responsive member in said metering pump.

5. An atomizing pump adapted for use in an oil burner comprising a main body having a pair of overlapping cylindrical chambers therein of different diameters, means forming a discharge outlet from the smaller of said chambers, means forming an inlet for air and for oil to said larger chamber on the opposite side of said body from said outlet, a rotor of smaller diameter than said larger chamber mounted therein for rotation eccentrically thereof, a valve in the smaller of said chambers, a pin located concentrically with said smaller chamber and forming a pivot supporting said valve for rocking movement, said valve including curved portions at either side of said pin concentric with said smaller chamber and of substantially the same radius for continuous engagement with the periphery of said smaller chamber to prevent communication between said inlet and said outlet through said smaller chamber, said valve having a reduced portion intermediate said curved portions and adjacent said larger chamber for receiving said rotor, said valve also including a tip portion adjacent said discharge outlet for engaging the periphery of said rotor, said valve having a further reduced portion at the opposite side thereof from said larger chamber and providing space in said smaller chamber, a torsion spring located in said space for biasing said valve into continuous contact of said tip portion thereof with said rotor to prevent the passage of fluid between said valve and said rotor as said valve rocks in response to rotation of said rotor, said concentric positioning of said pin in said smaller chamber providing substantial equalization of the pressures on said valve with relation to the pivotal axis thereof, and said torsion spring being mounted on said pin to provide a balanced bias about the pivotal axis of said valve with substantial freedom from side thrust.

6. An atomizing pump adapted for use in an oil burner comprising a main body having a pair of overlapping cylindrical chambers therein of different diameters, means forming a discharge outlet from the smaller of said chambers, means forming an inlet for air and for oil from said metering pump to said larger chamber on the opposite side of said body from said outlet, a rotor of smaller diameter than said larger chamber mounted therein for rotation eccentrically thereof, a valve in the smaller of said chambers, a pivot pin supporting said valve for rocking movement in said smaller chamber and located substantially concentric with said chamber, said valve including portions on opposite sides of said pin arranged for continuous engagement with the periphery of said smaller chamber to prevent communication therethrough between said inlet and said outlet, said valve including a tip portion intermediate said chamber-engaging portions adapted to engage the periphery of said rotor, and a torsion spring of the horseshoe type mounted on said spring for biasing said valve into continuous contact of said tip portion thereof with said rotor to prevent the passage of fluid between said valve and said rotor as said valve rocks in response to rotation of said rotor, said spring including portions engaging said valve in uniformly spaced relation on both sides of the axial center of said valve to maintain substantially uniform pressure contact between said tip portion of said valve and said rotor.

7. An atomizing pump adapted for use in an oil burner comprising a main body having a pair of overlapping cylindrical chambers therein of different diameters, means forming a discharge outlet from the smaller of said chambers, means forming an inlet for air and for oil to said larger chamber on the opposite side of said body from said outlet, a rotor of smaller diameter than said larger chamber mounted therein for rotation eccentrically thereof, a valve mounted for rocking movement in the smaller of said chambers and on the axis thereof, said valve including a portion arranged for continuous engagement with the periphery of said smaller chamber to prevent communication therethrough between said inlet and said outlet, said valve also including a tip portion adapted to engage the periphery of said rotor, spring means in said body for biasing said valve in the direction to maintain said valve in continuous contact of said tip portion thereof with said rotor to prevent the passage of fluid between said tip portion and said rotor as said valve rocks on said axis in response to rotation of said rotor, and said spring means including means for applying the biasing force thereof to said valve in equally balanced relation with the central radial plane of said valve to establish substantially uniform pressure along said tip portion of said valve with respect to said rotor.

References Cited in the file of this patent UNITED STATES PATENTS 119,482 Ward Oct. 3, 1871 996,984 Grindrod July 4, 1911 1,012,237 Bond Dec. 19, 1911 1,031,072 inney July 2, 1912 1,758,298 Teesdale May 13, 1930 1,760,699 Hult May 27, 1930 1,817,051 Williams Aug. 4, 1931 1,971,601 Dilg Aug. 28, 1934 

